Objective To retrospectively summarize the normal reference range of trachea wall thickness,lumen diameter,wall area and wall area ratio[WA%=mean wall area/(mean wall area+lumen area)]of Chinese healthy adults,and its related factors. Also,to observe the difference of inner diameter between superior and inferior bronchus.Methods Based on computer measurement techniques of bronchus,a CT quantitative analysis was carried out in 701 cases of normal healthy people who had negative results in lung cancer screening of health examination at our hospital.Results The value of trachea wall thickness,lumen diameter,wall area and wall area ratio was(1.322 mm,18.024 mm,78.93 mm2 ,0.27)respectively.In different gender,the trachea wall thickness,lumen diameter,wall area and wall area ratio had statistical significance (P<0.05).Also,they had good consistency with gender (r=-0.512,-0.472,-0.559,0.315).In different gender and age,the difference of inner diameter between the superior bronchus and inferior bronchus was always a positive value.Conclusion The CT quantitative analysis method has advantages of convenience,direct-vie-wing and accuracy.It is good for quantitative detection and research of bronchus structure.Bronchial wall thickness,lumen diameter, wall area and wall area ratio have significant difference because of gender.The inner diameter of superior bronchus is always greater than that of the inferior bronchus.

Objective To investigate the application value of Revolution CT dual-low technique coronary angiography in coronary heart disease.Methods One hundred patients with suspected coronary heart disease were retrospectively selected and randomly divided into control group and observation group,who all were examined by Revolution CT.In the control group(50 cases),the tube voltage was 120 kV,the contrast agent iohexol was 350 mg I/mL,and the dose of contrast agent was 1 mL/kg.In the observation group(50 cases),the tube voltage was 100 kV,the contrast agent iohexol was 350 mg I/mL,and the dose of contrast agent was 0.8 mL/kg.All patients underwent coronary digital subtraction angiography(DSA)examination at the same time.The image quality(subjective and objective evaluation indexes)and radiation dose of the two groups were compared,the diagnostic value of the two methods for coronary artery stenosis was compared,and the diagnostic consistency with coronary DSA between the two methods were compared using the Kappa test,as well as the typical coronary images of the two groups were analyzed.Results There were no significant differences in the sub-jective image quality grade and excellence rate between the observation group and the control group(P＞0.05).The CT value and noise of the observation group were higher than those of the control group(P＜0.05).There were no statistically significant differ-ences in the signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of the right coronary proximal and the left coronary main trunk between the two groups(P＞0.05).Compared with the control group,the volume CT dose index(CTDIvol),dose length product(DLP),and effective dose(ED)were lower in the observation group(P＜0.05).Compared with the results of coronary DSA,the positive predictive value,negative predictive value,sensitivity,specificity and accuracy of the two methods were＞80％,while there was no significant difference between the two groups(P＞0.05).The Kappa value of the observation group versus coronary DSA diagnosis was 0.871,the Kappa value of the control group ver-sus coronary DSA diagnosis was 0.889,and the consistency of both methods versus coronary DSA diagnosis was good.Conclusion Revolution CT dual-low technigue coronary angiography has good diagnostic value for coronary heart disease and can significantly reduce the radiation dose while ensuring image quality.

Objective: To explore the differences among three methods of nucleic acid extraction and three kinds of real-time fluorescence quantitative PCR instrument. Methods: Twenty-five respiratory virus nucleic acid and 25 enterovirus nucleic acid positive samples were with selected at random and nucleic acids were extracted by using three methods (method A, B, and C). The results among different methods were analyzed by randomized block design. 25 respiratory viral nucleic acid positive specimens and enterovirus nucleic acid positive samples were detected by using three kinds of real-time fluorescence quantitative PCR instrument (instrument A, B, and C). The results among different instruments were analyzed by randomized block design. Results: There was a significant difference among three methods of nucleic acid extraction in results(χ²=42.9162, P<0.001), in which method A and C had not significant difference(Z=0.837, P=0.3816>0.05), while method A vs. B, B vs. C were significantly different(Z=7.025, P<0.001; Z=7.9, P<0.001). There was also a significant difference among three kinds of real-time fluorescence quantitative PCR instrument in results(χ²=23.773, P<0.001), in which instrument B and C had no significant difference(Z=0.75, P=0.4533>0.05), while instrument A vs. B, A vs. C were significantly different(Z=5.70, P<0.001; Z=6.45, P<0.001). Conclusions There is difference among different methods and instruments in the test results under the same condition, which call for options in practical work according to need.